@ wilyflier,
The Met physistists swore there wasnt enough water at 25000ft to cause a Viscount complete 4 engine shut down over the Alps in1958. Their figures were out by an enormous factor , something like100/1. So we had to modify all Bristol Proteus engines as a result.
Not to be nit-picking, to my knowledge the Bristol Proteus was indeed prone to icing but was married to the Britannia, not the Viscount. The Viscount had RR Darts.
@gas path,
Now (in the last week!) the complete manifolding from the other tank has been removed to make up the complete a/c assembly to see if that makes any difference to the test results.
With regards to "the other tank", that does not mean only the other main tank but I assume that also includes the fuel lines and override jettison pumps from the center tank?
Green-dot